1987-91 heater core replacement

Thanks in advance if anyone can provide some expertise. I need to change the heater core in my 90 Bonneville LE. It's leaking on the inside of the car. I've done this on other cars, but I'd like to know if I have to remove the dash assembly in order to gain enough clearance to get the core out. I've got a shop manual, but it doesn't describe in enough detail what really needs to come off. On another note, I wonder if it started leaking when I changed my heater hoses that run to the core. Hmmm. No, I was fairly careful getting the hoses off.

Thanks!

Its not as hard as it looks, here-
http://www.bonnevilleclub.com/forum/viewtopic.php?t=9034

You dont have to take the dash out, just the access panel on the passengers side. I removed the computer & heater controls to get more room to work under the dash (theres a cover on the core thats kind of tricky to get out of the way, but it can be done). Youve already done the hoses going to the core, that was the hardest thing I found. Just no room in that area! :banghead: